Isoquinoline Alkaloids and Homoisoflavonoids from Drimiopsis barteri Bak and D. burkei Bak

Abstract

The powdered bulbs and leaves of Drimiopsis barteri yielded two novel isoquinoline alkaloids: 5-hydroxy-7,2′,3′,4′-tetramethoxy{2H-1-}benzopyran [4,3-c]isoquinoline and 6-hydroxy-7,2′,3′,4′-tetramethoxy{2H-1-}benzopyran [4,3-c]isoquinoline, three new scillascillins: 5,7-dihydroxy-2′,3′,4′-trimethoxyspiro-{2H-1-benzopyran-7′-bicyclo [4.2.0]octa[1,3,5]-triene}-4-one, 5-hydroxy-7,2′,3′,4′-tetramethoxyspiro{2H-1-benzopyran-7′-bicyclo [4.2.0]octa[1,3,5]-triene}-4-one and 5,2′,4′-trihydroxy-7,3′-dimethoxyspiro{2H-1-benzopyran-7′-bicyclo [4.2.0]octa[1,3,5]-triene}-4-one, and a tetrahydroxyhomo-isoflavanone: 5,6,7-trihydroxy-3-(4-hydroxybenzyl)chroman-4-one. The bulbs of Drimiopsis burkei gave three new metabolites: the first scillascillin, mentioned above, and two xanthones: 1,6-dihydroxy-2,3-dimethoxy-8-methylxanthone and 1,4-dihydroxy-2,3,6-trimethoxy-8-methylxanthone. Seventeen known compounds were isolated from both plants. Structures were elucidated based on detailed 1-, and 2D-NMR spectroscopic and MS analyses.